US10495387B2 - Multi-layer wick structures with surface enhancement and fabrication methods - Google Patents
Multi-layer wick structures with surface enhancement and fabrication methods Download PDFInfo
- Publication number
- US10495387B2 US10495387B2 US15/722,589 US201715722589A US10495387B2 US 10495387 B2 US10495387 B2 US 10495387B2 US 201715722589 A US201715722589 A US 201715722589A US 10495387 B2 US10495387 B2 US 10495387B2
- Authority
- US
- United States
- Prior art keywords
- mold
- layer
- porous
- porous wick
- wick layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related, expires
Links
- 238000000034 method Methods 0.000 title claims abstract description 65
- 238000004519 manufacturing process Methods 0.000 title claims description 20
- 239000002923 metal particle Substances 0.000 claims abstract description 72
- 238000005245 sintering Methods 0.000 claims abstract description 63
- 239000002245 particle Substances 0.000 claims abstract description 43
- 239000000945 filler Substances 0.000 claims abstract description 26
- 239000007788 liquid Substances 0.000 claims description 86
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 22
- 229910052802 copper Inorganic materials 0.000 claims description 21
- 239000010949 copper Substances 0.000 claims description 21
- 229910052751 metal Inorganic materials 0.000 claims description 9
- 239000002184 metal Substances 0.000 claims description 9
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 claims description 4
- 238000003754 machining Methods 0.000 claims description 3
- 238000003825 pressing Methods 0.000 claims 1
- 239000012809 cooling fluid Substances 0.000 description 30
- 239000000463 material Substances 0.000 description 9
- 238000009835 boiling Methods 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- 230000008569 process Effects 0.000 description 7
- 230000009471 action Effects 0.000 description 6
- 230000008878 coupling Effects 0.000 description 5
- 238000010168 coupling process Methods 0.000 description 5
- 238000005859 coupling reaction Methods 0.000 description 5
- 238000001704 evaporation Methods 0.000 description 5
- 238000001816 cooling Methods 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- 238000012546 transfer Methods 0.000 description 3
- 238000009736 wetting Methods 0.000 description 3
- 239000004020 conductor Substances 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 230000017525 heat dissipation Effects 0.000 description 2
- 238000003698 laser cutting Methods 0.000 description 2
- 230000000116 mitigating effect Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000002086 nanomaterial Substances 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- -1 without limitation Substances 0.000 description 2
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000010603 microCT Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000011343 solid material Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
- F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
- F28D15/04—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes with tubes having a capillary structure
- F28D15/046—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes with tubes having a capillary structure characterised by the material or the construction of the capillary structure
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/10—Sintering only
- B22F3/11—Making porous workpieces or articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/10—Sintering only
- B22F3/11—Making porous workpieces or articles
- B22F3/1103—Making porous workpieces or articles with particular physical characteristics
- B22F3/1115—Making porous workpieces or articles with particular physical characteristics comprising complex forms, e.g. honeycombs
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/26—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass heat exchangers or the like
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F13/00—Arrangements for modifying heat-transfer, e.g. increasing, decreasing
- F28F13/003—Arrangements for modifying heat-transfer, e.g. increasing, decreasing by using permeable mass, perforated or porous materials
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F21/00—Constructions of heat-exchange apparatus characterised by the selection of particular materials
- F28F21/08—Constructions of heat-exchange apparatus characterised by the selection of particular materials of metal
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
- H01L23/42—Fillings or auxiliary members in containers or encapsulations selected or arranged to facilitate heating or cooling
- H01L23/427—Cooling by change of state, e.g. use of heat pipes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/02—Compacting only
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/10—Sintering only
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/10—Sintering only
- B22F3/11—Making porous workpieces or articles
- B22F3/114—Making porous workpieces or articles the porous products being formed by impregnation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
- B22F7/002—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of porous nature
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
- B22F7/02—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite layers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
- B22F7/02—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite layers
- B22F7/04—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite layers with one or more layers not made from powder, e.g. made from solid metal
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P2700/00—Indexing scheme relating to the articles being treated, e.g. manufactured, repaired, assembled, connected or other operations covered in the subgroups
- B23P2700/09—Heat pipes
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
- C22C1/0425—Copper-based alloys
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
- F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
- F28D15/0233—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes the conduits having a particular shape, e.g. non-circular cross-section, annular
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F2255/00—Heat exchanger elements made of materials having special features or resulting from particular manufacturing processes
- F28F2255/18—Heat exchanger elements made of materials having special features or resulting from particular manufacturing processes sintered
Definitions
- the present specification generally relates to apparatuses and methods of fabricating apparatuses for cooling heat generating devices such as power electronic devices and, more specifically, to multi-layer porous wick structures with surface enhancement features and methods of fabricating multi-layer porous wick structures with surface enhancement features for improved heat dissipation performance of the multi-layer wick structure.
- Heat sinking devices may be coupled to a heat-generating device, such as a power electronics device, to remove heat and lower the maximum operating temperature of the heat-generating device.
- Cooling fluid may be used to receive heat generated by the heat-generating device by convective thermal transfer and remove such heat from the heat-generating device. For example, a jet of cooling fluid may be directed such that it impinges a surface of the heat-generating device.
- Another method may include removing heat from a heat-generating device by passing cooling fluid between and around a finned heat sink made of thermally conductive material, such as aluminum.
- Vapor chambers may offer a viable solution to dissipating localized hotspots while maintaining an acceptable level of reliability.
- Vapor chambers may transfer heat from hotspots to porous wick structures having cooling fluid that boils within a sealed vapor chamber. The vapor rises away from the localized hotspot extracting heat with the vapor and condensing over an adjacent porous surface, which through capillary action within interconnected porous structures of the vapor chamber cooling fluid is transferred back to hotspots for further heat extraction through boiling.
- current methods of fabricating the porous wick structures face challenges that affect the wicking process and decrease wick performance, such as subtractive processes, which lead to fused particles in critical regions of the porous wick layers reducing their overall performance.
- interconnected structures for returning cooling fluid to hotspots reduce the area available for boiling of the cooling fluid thus reducing cooling performance.
- a method for fabricating a multi-layer porous wick structure may include providing a first mold set including a negative mold and a positive mold, introducing metal particles in a cavity of the negative mold defining a first porous wick layer, and sintering the metal particles at a first sintering temperature for a first sintering time within the negative mold while interfaced with the positive mold to form the first porous wick layer, where the first porous wick layer includes a first surface opposite a second surface and a plurality of porous liquid supply posts extend from the first surface away from the second surface.
- the method may further include providing a second mold set including a negative mold and a positive mold corresponding to the negative mold, where the negative mold includes a cavity defined by one or more sidewalls enclosing a base surface offset from a negative mold top surface and the cavity is contoured for receiving the first porous wick layer and assembling the first porous wick layer with the negative mold of the second mold set.
- the method may further include introducing filler particles into the negative mold of the second mold set, where the filler particles form a sacrificial layer with the first surface and plurality of porous liquid supply posts of the first porous wick layer such that a portion of the plurality of porous liquid supply posts remain free of the sacrificial layer, introducing metal particles in the negative mold of the second mold set with the first porous wick layer and the sacrificial layer, and sintering the metal particles at a second sintering temperature for a second sintering time thereby forming the multi-layer porous wick structure including the first porous wick layer including a plurality of porous liquid supply posts coupled to a second porous wick layer.
- the method for fabricating a multi-layer porous wick structure may include providing a first mold set including a negative mold and a positive mold, introducing metal particles in a cavity of the negative mold defining a first porous wick layer and sintering the metal particles within the negative mold while interfaced with the positive mold to form the first porous wick layer, where the first porous wick layer includes a first surface opposite a second surface, a plurality of porous liquid supply posts extending from the first surface away from the second surface, and a plurality of through-holes extending between the first surface and the second surface of the first porous wick layer.
- the method may further include providing a second mold set including a negative mold and a positive mold corresponding to the negative mold, where the negative mold includes a cavity defined by one or more sidewalls enclosing a base surface offset from a negative mold top surface and the cavity is contoured for receiving the first porous wick layer and receiving the first porous wick layer in the negative mold of the second mold set.
- the method may further include introducing filler particles into the negative mold of the second mold set, where the filler particles form a sacrificial layer with the first surface and plurality of porous liquid supply posts of the first porous wick layer such that a portion of the plurality of porous liquid supply posts remain free of the sacrificial layer, introducing metal particles in the negative mold of the second mold set with the first porous wick layer and the sacrificial layer, applying a sintering pressure to the metal particles with the positive mold of the second mold set, and sintering the metal particles at a sintering temperature for a sintering time, thereby forming a second porous wick layer coupled to the plurality of porous liquid supply posts of the first porous wick layer.
- the method for fabricating a multi-layer porous wick structure may include providing a first mold set including a negative mold and a positive mold, introducing metal particles in a cavity of the negative mold of the first mold set, and sintering the metal particles in the first mold set to form a first porous wick layer including a plurality of porous liquid supply posts extending from the first porous wick layer and a plurality of surface enhancement features formed with the first porous wick layer.
- the method may further include providing a second mold set including a negative mold and a positive mold corresponding to the negative mold, where the negative mold includes a cavity contoured for receiving the first porous wick layer and assembling the negative mold of the second mold set with the first porous wick layer with the negative mold of the second mold set.
- the method may further include introducing filler particles into the negative mold of the second mold set, where the filler particles form a sacrificial layer over the first porous wick layer and the sacrificial layer extends no more than the height of the plurality of porous liquid supply posts and compacting the filler particles with a forming mold including cavities for receiving the filler particles to fabricate a sacrificial layer that extends above the plurality of porous liquid supply posts in defined sections while maintaining exposure to at least a portion of the plurality of porous liquid supply posts.
- the method may further include introducing metal particles in the negative mold of the second mold set having the first porous wick layer and the sacrificial layer and sintering the metal particles thereby forming a second porous wick layer coupled to the plurality of porous liquid supply posts of the first porous wick layer.
- FIG. 1 schematically depicts a perspective view of an example multi-layer wick structure according to one or more embodiments shown and described herein;
- FIGS. 2A & 2B schematically depict a perspective view and side view of an example base layer of a multi-layer wick structure having surface enhancement features according to one or more embodiments shown and described herein;
- FIG. 2C schematically depicts multiple cross-sections of example surface enhancement features for a multi-layer wick structure according to one or more embodiments shown and described herein;
- FIG. 3 is a flowchart depicting a method of fabricating a multi-layer porous wick structure according to one or more embodiments shown and described herein;
- FIG. 4 schematically depicts a perspective view of an example negative mold of a first mold set according to one or more embodiments shown and described herein;
- FIG. 5 schematically depicts a perspective view of an example first mold set assembly having a positive mold and a negative mold according to one or more embodiments shown and described herein;
- FIG. 6A schematically depicts a perspective view of an example first mold set assembly according to one or more embodiments shown and described herein;
- FIG. 6B schematically depicts a cross-sectional view of the example first mold set assembly of FIG. 6A according to one or more embodiments shown and described herein;
- FIG. 8A schematically depicts a perspective view of an example sacrificial layer formed with the first porous wick layer in the negative mold of the second mold set according to one or more embodiments shown and described herein;
- FIG. 8B schematically depicts a cross-sectional view of the example negative mold of the second mold set in FIG. 8A having a sacrificial layer formed with the first porous wick layer according to one or more embodiments shown and described herein;
- FIG. 8C schematically depicts a cross-sectional view of an example second mold set for forming surface enhancement features within the sacrificial layer according to one or more embodiments shown and described herein;
- FIG. 9B schematically depicts a cross-sectional view of the example second mold set assembly of FIG. 9A according to one or more embodiments shown and described herein;
- FIG. 9C schematically depicts a cross-sectional view of an example second mold set assembly for forming a second porous wick layer with surface enhancement features according to one or more embodiments shown and described
- FIG. 10 schematically depicts a cross-sectional view of an example mold set for forming a multi-layer wick structure having a liquid supply wick according to one or more embodiments shown and described herein;
- FIG. 11 schematically depicts a cross-sectional view of an example multi-layer wick structure having a liquid supply wick according to one or more embodiments shown and described herein;
- FIG. 12 schematically depicts a perspective view of another example negative mold of another example first mold set according to one or more embodiments shown and described herein;
- FIG. 13 schematically depicts a perspective view of an the example negative mold of the example first mold set with metal particles prior to sintering according to one or more embodiments shown and described herein;
- FIG. 14A schematically depicts a perspective view of an example first mold set assembly having a positive mold and a negative mold for sintering a first porous wick layer according to one or more embodiments shown and described herein;
- FIG. 14B schematically depicts a cross-sectional view of an example first mold set assembly of FIG. 14A having a positive mold and a negative mold for sintering a first porous wick layer according to one or more embodiments shown and described herein;
- FIG. 15 schematically depicts a perspective view of another example first porous wick layer according to one or more embodiments shown and described herein;
- FIG. 16 schematically depicts a perspective view of another example negative mold of a second mold set receiving a first porous wick layer according to one or more embodiments shown and described herein;
- FIG. 17 schematically depicts a perspective view of the example negative mold of the second mold set assembled with the first porous wick layer according to one or more embodiments shown and described herein;
- FIG. 18A schematically depicts a perspective view of an example assembly of the second mold set having a positive mold and a negative mold according to one or more embodiments shown and described herein;
- FIG. 18B schematically depicts a cross-sectional view of the example second mold set assembly of FIG. 18A according to one or more embodiments shown and described herein;
- FIG. 19 schematically depicts a perspective view of the example second mold set assembly having a positive mold and a negative mold for sintering an second porous wick layer according to one or more embodiments shown and described herein;
- FIG. 20 schematically depicts a perspective view of an example multi-layer porous wick structure post sintering without vapor vents according to one or more embodiments shown and described herein;
- FIG. 21 schematically depicts a perspective view of an example multi-layer porous wick structure post sintering with vapor vents according to one or more embodiments shown and described herein;
- FIG. 22 schematically depicts a cross-sectional view of an example mold set assembly for forming a sacrificial layer with the first porous wick layer according to one or more embodiment shown and described herein;
- FIG. 23 schematically depicts a cross-sectional view of an example first porous wick layer having a sacrificial layer according to one or more embodiment shown and described herein;
- FIG. 24 schematically depicts a cross-sectional view of an example mold assembly for forming a liquid supply wick and a second porous wick layer with the first porous wick layer according to one or more embodiment shown and described herein;
- FIG. 25 schematically depicts a cross-sectional view of an example multi-layer wick structure having a liquid supply wick according to one or more embodiment shown and described herein;
- FIG. 26 schematically depicts a perspective view of an example vapor chamber with an array of multi-layer porous wick structures according to one or more embodiment shown and described herein;
- FIG. 27 schematically depicts a perspective view of an example vapor chamber attached to heat generating devices according to one or more embodiment shown and described herein.
- FIG. 1 generally depicts an example multi-layer porous wick structure 100 for implementation in a vapor chamber device suitable for extracting heat, for example, from power electronic packages.
- the multi-layer porous wick structure 100 depicted in FIG. 1 is a two-layer porous wick structure having a first porous wick layer 10 defining a base wick layer 10 coupled to a second porous wick layer 20 defining a cap wick layer 20 through a plurality of porous liquid supply posts 30 forming interstitial spaces around the plurality of porous liquid supply posts 30 and between the base wick layer 10 and cap wick layer 20 .
- the plurality of porous liquid supply posts 30 may have different cross-sections, such as, without limitation, circular, triangular, square, or other closed shape cross-sections.
- the plurality of porous liquid supply posts 30 may also have non-uniform cross-sections along their length, for example, the plurality of porous liquid supply posts 30 may be tapered.
- a porous wick layer with tapered porous liquid supply posts may allow for easier removal from the mold after sintering.
- the multi-layer porous wick structure 100 also includes a plurality of through-holes 40 defining vapor vents 40 in the cap wick layer 20 .
- the multi-layer porous wick structure 100 may also include a liquid supply wick (not shown) coupled to sidewalls 11 of the base wick layer 10 and the sidewalls 21 of the cap wick layer 20 . Additionally, the multi-layer porous wick structure 100 may include additional layers (not shown), for example, a third porous wick layer defining a condensing layer coupled to the second porous wick layer 20 defining the cap wick layer 20 through additional porous liquid supply posts 30 forming interstitial spaces around the plurality of porous liquid supply posts 30 and between the condensing layer and cap wick layer 20 thereby defining a vapor core.
- additional layers not shown
- the multi-layer porous wick structure 100 may further be enclosed in a vapor chamber and include cooling fluid.
- An appropriate cooling fluid may be determined based on the operating temperature ranges to effect cooling through the vapor chamber.
- the cooling fluid may be water.
- the thermophysical properties of water may be ideal for operating temperatures from about 0 degrees Celsius to about 200 degrees Celsius. While water is used in the following example it is conceivable that other cooling fluids may be used other than water.
- the heat generated by a device coupled to a vapor chamber conducts through the vapor chamber evaporator wall into the base wick layer 10 containing cooling fluid in the porous structure of the base wick layer 10 .
- the cooling fluid begins to boil and evaporate from the base wick layer 10 as the temperature increases.
- the vapor from the boiling cooling fluid rises from the base wick layer 10 into the interstitial spaces around the plurality of porous liquid supply posts 30 and between the base wick layer 10 and the cap wick layer 20 .
- the vapor further travels through the plurality of through-holes 40 defining vapor vents 40 in the cap wick layer 20 .
- the vapor As the vapor travels from the interstitial spaces through the vapor vents 40 the vapor begins to condense. Some vapor may condense on and into the porous structure of the cap wick layer 20 . Through capillary action, the condensed cooling fluid is transported through the cap wick layer 20 and the plurality of porous liquid supply posts 30 back into the base wick layer 10 . The capillary action may be sufficient to feed hotspots of the base wick layer 10 with cooling fluid to continue to promote boiling and evaporation at the hotspots of the base wick layer 10 and prevent dry out of the base wick layer 10 .
- Vapor that does not condense with the cap wick layer 20 may travel through the vapor vents 40 to an additional cap wick layer 20 or a condensing layer where the vapor condenses and capillary action returns the condensed cooling fluid to the base wick layer 10 through the plurality of porous liquid supply posts 30 .
- the condensing layer may be a metal plate or porous wick layer or a combination thereof and optionally formed through methods described herein.
- a porous side wick on the walls (not shown) or liquid supply wick (not shown) of the vapor chamber may couple and promote capillary transport of the cooling fluid between the condensing layer, cap wick layer and base wick layer.
- a plurality of porous liquid supply posts may couple a condensing layer to a cap wick layer as well as a cap wick layer to a base wick layer.
- the plurality of porous liquid supply posts may be optimized between the condensing layer and cap wick layer, for example, such that fewer porous liquid supply posts are positioned between the condensing layer and the cap wick layer than the cap wick layer and the base wick layer. This optimization will prevent excess heat conduction through the plurality of porous liquid supply posts and cap wick layer to the condensing layer.
- a liquid supply wick (not shown) may feed the base wick layer 10 with cooling fluid.
- cooling fluid is introduced to the liquid supply wick during assembly of the vapor chamber.
- the liquid supply wick may receive cooling fluid from a reservoir of cooling fluid or cap wick layers 20 coupled to the liquid supply wick.
- a base wick layer 10 may include surface enhancement features 50 to improve the boiling and evaporating process of the cooling fluid at hotspots.
- FIG. 2C generally depicts several cross-sectional examples of surface enhancement features 50 .
- surface enhancement features 50 may operate to increase the surface area available to promote boiling and evaporation. The additional surface area may offset surface area lost to the presence of the plurality of porous liquid supply posts 30 or increase the surface area in hotspot locations to promote improved heat transfer.
- surface enhancement features 50 may be included in the cap wick layer 20 or additional layers to increase the surface area available for condensing vapor to liquid cooling fluid.
- the surface enhancement features 50 depicted are dome shaped protrusions from the base wick layer 10 disposed between and around the plurality of porous liquid supply posts 30 .
- the surface enhancement features 50 may be disposed uniformly across a base wick layer 10 or positioned to correspond to localized hotspots of the base wick layer 10 during operation with a heat-generating device. Additionally, the surface enhancement features 50 may vary in size and shape across the base wick layer 10 .
- FIG. 2C depicts some cross-sectional non-limiting examples of surface enhancement features 50 .
- the surface enhancement features 50 may be protrusions from the base wick layer 10 where the surface 25 of the base wick layer 10 opposing the surface enhancement features 50 is generally planar and does not include surface enhancement features 50 thereby capable of coupling with a substrate 60 , for example, without limitation, a metal plate which is optionally a copper plate.
- a metal plate which is optionally a copper plate.
- the inverse surface enhancement feature 50 ′ may couple with a substrate 60 ′, for example, without limitation, a metal plate, which is optionally, a copper plate including the surface enhancement feature 50 .
- the multi-layer porous wick structure 100 and corresponding vaper chamber components may be formed of various materials.
- the multi-layer porous wick structure 100 is formed from a thermally conductive metal or alloy, such as, without limitation, copper.
- the material forming the multi-layer wick structure is hydrophilic, e.g., where the cooling fluid is water, and is a conductive material.
- a non-limiting example is sintered copper powder or copper particles that comprise superhydrophilic nanostructures.
- the wetting with a liquid of a surface of a material will be described in relation to a contact angle at which the liquid-vapor interface meets the solid-liquid interface.
- a wettable surface for example, hydrophilic if water is the cooling fluid, is any surface with a contact angle of less than 90 degrees, i.e., low contact angle, which indicates that wetting of the surface is very favorable, and a liquid will likely spread over the surface and in the case of a porous material, may spread into the material.
- a nonwettable surface for example, hydrophobic if water is the cooling fluid is any surface with a contact angle of greater than 90 degrees, i.e., high contact angle, which indicates that wetting of the surface is unfavorable, so a liquid will likely minimize contact with the surface and form a compact liquid droplet on the surface.
- a superhydrophilic surface for example, if water is the cooling fluid, refers to a surface on which a liquid will uniformly spread such that it forms a thin conformal liquid layer rather than a droplet with a measurable contact angle. Therefore, the above-mentioned superhydrophilic nanostructures are structures that either have superhydrophilic surfaces, or in combination form a superhydrophilic surface.
- the term “metal particles” refers various materials that may be used in place of or in combination with metal particles, for example, copper particles. Additionally, the term “particles” may refer to particles and or powders.
- multi-layer porous wick structures 100 Various fabrication methods for fabricating multi-layer porous wick structures 100 will now be described in more detail herein.
- the following fabrication methods refer to the multi-layer porous wick structure 100 similar to the structure shown and described in FIG. 1 .
- multi-layer porous wick structures 100 having different shapes, sizes and layouts are within the scope of the fabrication methods described herein.
- other multi-layer porous wick structures 100 may include more than two layers or various layouts, sizes and shapes defining the porous liquid supply posts 30 and vapor vents 40 or a variety of surface enhancement features 50 formed with the layers of the multi-layer porous wick structure 100 .
- Methods for fabricating a multi-layer porous wick structure 100 described herein generally include step 110 of providing a first mold set comprising a negative mold and a positive mold, step 120 , introducing metal particles into the negative mold of the first mold set, and step 130 , sintering the metal particles in the negative mold of the first mold set where pressure is applied to the metal particles with the positive mold of the first mold set thereby forming a first porous wick structure having a plurality of porous liquid supply posts 30 .
- the method further generally includes step 140 of providing a second mold set comprising a positive mold and a negative mold configured to receive the first porous wick structure, step 150 , introducing filler particles to form a sacrificial layer with the first porous wick layer in the negative mold of the second mold set, step 160 , introducing metal particles with the sacrificial layer and the first wick layer in the negative mold of the second mold set and step 170 , sintering the metal particles in the negative mold of the second mold set where pressure is applied to the metal particles by the positive mold of the second mold set.
- the sintering of the metal particles in the negative mold of the second mold set, in step 170 forms a second porous wick layer coupled to the porous liquid supply posts 30 of the first porous wick layer.
- the aforementioned general fabrication method may be further defined to accommodate variations in order by which a multi-layer porous wick structure 100 is fabricated, for example, a multi-layer porous wick structure 100 using the methods described herein may be formed from a base wick layer 10 to a cap wick layer 20 or a cap wick layer 20 to a base wick layer 10 .
- steps previously described are presented in a particular order, it is within the scope of the fabrication methods described herein that steps may be carried out in a variety of orders and may include additional intervening steps.
- fabrication methods may include molds for forming vapor vents 40 in the cap wick layer 20 or liquid supply wicks coupling the base wick layer 10 and the cap wick layer 20 or surface enhancement features 50 .
- the fabrication methods described herein may also include or be integrated with methods of fabricating a multi-layer porous wick structure 100 with a vapor chamber.
- the first method of fabricating a multi-layer porous wick structure 100 described below relates to forming the multi-layer porous wick structure 100 from a cap wick layer 20 to a base wick layer 10 .
- the second method of fabricating a multi-layer porous wick structure 100 described below relates to forming the multi-layer porous wick structure 100 from a base wick layer 10 to a cap wick layer 20 .
- a negative mold 210 of a first mold set 200 for forming a first porous wick layer 310 defining a cap wick layer is depicted.
- the negative mold 210 comprises a first surface 212 , a second surface 214 , one or more sidewalls 216 , a plurality of holes 218 and a plurality of posts 220 .
- the second surface 214 is offset from the first surface 212 .
- the one or more sidewalls 216 extend around a perimeter of the second surface 214 and between the first surface 212 and the second surface 214 .
- the second surface 214 and the one or more sidewalls 216 define a cavity 222 in the first surface 212 of the negative mold 210 of the first mold set 200 .
- the cavity 222 depicted in FIG. 4 has a perimeter generally defined by a square and has a generally planar second surface 214 . However, in other embodiments the cavity 222 may have a perimeter defined by a circle or other closed shape.
- the second surface 214 may include negative or positive contours or surface enhancement features to form a corresponding positive or negative contour or surface enhancement in the first porous wick layer 310 formed within the cavity 222 of the negative mold 210 of the first mold set 200 .
- the plurality of holes 218 extend from the second surface 214 into the negative mold 210 , i.e., generally away from a plane defined by the first surface 212 .
- the plurality of holes 218 are cavities for forming the plurality of porous liquid supply posts 330 (as shown in FIG. 7 ) as described herein.
- the plurality of holes 218 may vary in shape and size depending on the design requirements needed to increase or decrease capillary action through the plurality of porous liquid supply posts 330 to portions of the base wick layer or the need to increase or decrease surface area available for boiling and evaporating cooling fluid from the base wick layer.
- the shape and size of the plurality of holes 218 may be determined in response to mitigating localized hotspots of the base wick layer.
- the plurality of posts 220 form a plurality of through-holes 340 in the first porous wick layer 310 defining vapor vents in the resulting multi-layer porous wick structure 300 .
- the plurality of posts 220 extend from the second surface 214 toward the plane defined by the first surface 212 . In some embodiments, the plurality of posts 220 extend a height from the second surface 214 equal to or greater than the thickness of the first porous wick layer 310 to be formed. In some embodiments, the plurality of posts 220 extend a height that is at least equal to the depth of the cavity 222 defined by the offset of the second surface 214 from the first surface 212 of the negative mold 210 of the first mold set 200 . In other embodiments, the plurality of posts 220 extend from the second surface 214 to or above the plane defined by the first surface 212 of the negative mold 210 of the first mold set 200 .
- FIG. 5 an example first mold set 200 assembly comprising the negative mold 210 depicted in FIG. 4 and a positive mold 230 is depicted.
- Metal particles 224 are introduced in the negative mold 210 of the first mold set.
- the metal particles 224 fill the plurality of holes 218 of the negative mold 210 of the first mold set 200 .
- metal particles 224 may fill the cavity 222 from the second surface 214 of the negative mold 210 to the plane defined by the first surface 212 of the negative mold 210 .
- the metal particles 224 fill a portion of the cavity 222 of the negative mold 210 to a desired depth between the second surface 214 and the plane defined by the first surface 212 .
- metal particles 224 are not added beyond the tops 226 of the plurality of posts 220 , unless compression of the metal particles 224 by the positive mold 230 of the first mold set 200 results in a first porous wick layer 310 having a thickness less than the height of the plurality of posts 220 such that a plurality of through-holes 340 are formed by the plurality of posts 220 in the first porous wick layer 310 .
- the positive mold 230 of the first mold set comprises a plurality of holes 232 corresponding to the plurality of posts 220 in the negative mold 210 of the first mold set 200 .
- the negative mold 210 is filled with metal particles 224 up to the plane defined by the first surface 212 of the negative mold 210 .
- the plurality of posts 220 extend beyond the plane defined by the first surface 212 of the negative mold 210 to form corresponding plurality of through-holes 340 in the first porous wick layer 310 .
- the positive mold 230 of the first mold set 200 is aligned with the negative mold 210 of the first mold set 200 such that the plurality of posts 220 interface with the plurality of holes 232 .
- the plurality of holes 232 extend into the positive mold 230 of the first mold set 200 to a depth greater than the height of the plurality of posts 220 of the negative mold 210 . The greater depth allows the positive mold 230 to compress the metal particles 224 during sintering such that the plurality of posts 220 of the negative mold 210 will not bottom out against the base 234 of the plurality of holes 232 during sintering.
- the depth of the plurality of holes 232 is less than the height of the plurality of posts 220 of the negative mold 210 but sufficiently deep to allow for compaction of the metal particles 224 as shown in the cross-sectional view of FIG. 6B while maintaining a gap 228 between the plurality of posts 220 and the base 234 of the plurality of holes 232 .
- sintering is a process of forming a solid material by applying heat and pressure for a period of time while not melting the material to the point of liquefaction.
- sintering comprises applying a pressure and heat at an elevated temperature to the metal particles 224 in the first mold set for a period of time in a reducing or inert atmosphere. The sintering pressure and temperature are determined based on the type of particles being sintered and the desired porosity of the resulting multi-layer porous wick structure.
- the porosity of the multi-layer porous wick structure can be controlled by the sintering time and the sintering temperature.
- the sintering temperature is about 750 degrees Celsius to about 1000 degrees Celsius.
- the sintering temperature is 100 degrees Celsius to about 300 degrees Celsius or 590 degrees Celsius to about 620 degrees Celsius or 850 degrees Celsius to about 950 degrees Celsius or 740 degrees Celsius to about 780 degrees Celsius or 200 degrees Celsius to about 1600 degrees Celsius.
- the sintering time is about 1 hour to about 32 hours.
- the sintering time is optionally about 5 minutes, about 10 minutes, about 15 minutes, about 30 minutes, about 45 minutes, about 1 hour, about 6 hours, about 12 hours, about 18 hours, about 24 hours or about 30 hours.
- the higher the sintering temperature the shorter the sintering time required to achieve a desired degree of bonding between the particles in the particle compact.
- the porosity of the multi-layer porous wick structure may be examined through X-ray microtomography scanning and subsequently the sintering temperature and sintering time may be adjusted to achieve the desired porosity.
- the first porous wick layer 310 comprises a first surface 312 opposite a second surface 314 , one or more sidewalls 316 extending around a perimeter of the first porous wick layer 310 between the first surface 312 and the second surface 314 , a plurality of through-holes 340 extending between the first surface 312 and the second surface 314 and a plurality of porous liquid supply posts 330 extending from the first surface 312 to a height defined by the depth of the plurality of the holes 218 in the negative mold 210 of the first mold set 200 .
- the negative mold 410 of the second mold set 400 comprises a cavity 418 defined by a base surface 414 offset from a negative mold top surface 412 enclosed by one or more sidewalls 416 extending around a perimeter of the base surface 414 and between the cavity base surface 414 and the negative mold top surface 412 .
- the cavity 418 defined by the base surface 414 and one or more sidewalls 416 is contoured for receiving the first porous wick layer 310 .
- the second surface 314 of the first porous wick layer 310 is configured adjacent to the base surface 414 of the negative mold 410 of the second mold set 400 .
- the filler particles 360 are carbonate particles.
- the filler particles 360 are not limited to carbonate particles. Rather, the filler particles 360 may be any material that decomposes at the elevated sintering temperatures thereby leaving behind only features formed by the sintered particles.
- the filler particles 360 for example carbonate particles, decompose during a process referred to as a lost-carbonate sintering (LCS) process.
- LCS lost-carbonate sintering
- the filler particles 360 are compacted by an intermediate positive mold 430 .
- the intermediate positive mold 430 may have a generally planar surface for compacting the sacrificial layer, for example in FIG. 8B .
- contours 364 may be formed in the sacrificial layer 362 with an intermediate positive mold 430 such as, without limitation, the embodiment depicted in FIG. 8C .
- the intermediate positive mold 430 compacts the sacrificial layer 362 with a contoured surface 432 thereby forming contours 364 in the sacrificial layer 362 .
- metal particles 366 are introduced with the first porous wick layer 310 and the sacrificial layer 362 in the negative mold 410 of the second mold set 400 .
- FIGS. 9A, 9B and 9C an example second mold set 400 assembly having a positive mold 420 interfacing with the negative mold 410 is depicted.
- FIG. 9A depicts the assembly of the positive mold 420 and negative mold 410 .
- FIGS. 9B and 9C depict example cross-sections of the second mold set 400 assembly of FIG. 9A .
- the metal particles 366 are sintered with the first porous wick layer 310 having a sacrificial layer 362 without contours 364 for surface enhancement features.
- FIG. 9C depicts a cross-section of the second mold set 400 assembly where the sacrificial layer 362 includes contours 364 for surface enhancement features 350 to be formed in second porous wick layer 320 formed by sintering the metal particles 366 introduced within.
- the multi-layer porous wick structure 300 includes surface enhancement features 350 formed with the second porous wick layer 320 .
- the sintering of the metal particles 366 forms a second porous wick layer 320 coupled to the plurality of porous liquid supply posts 330 of the first porous wick layer 310 .
- the sacrificial layer 362 decomposes during the sintering process leaving a multi-layer porous wick structure 300 within the negative mold 410 of the second mold set 400 after sintering.
- a copper plate (not shown) may be included between the positive mold 420 of the second mold set 400 and the metal particles 366 over the sacrificial layer 362 in the negative mold 410 of the second mold set 400 .
- the copper plate may form the evaporator layer that contacts a heat-generating device or optionally be used to form the vapor chamber apparatus.
- the multi-layer porous wick structure 300 formed through the fabrication method described and depicted with reference to FIGS. 4-9C resembles the multi-layer porous wick structure 100 depicted in FIG. 1 .
- the negative mold 410 may be modified, for example, without limitation, the negative mold 410 may include an insert that can be selectively removed or a third mold set 400 ′ having a negative mold 410 ′ and a corresponding positive mold 420 ′ is provided.
- the negative mold 410 ′ still comprises a cavity 418 ′ defined by a base surface 414 ′ offset from a negative mold top surface 412 ′ enclosed by one or more sidewalls 416 ′ extending around a perimeter of the base surface 414 ′ and between the base surface 414 ′ and the negative mold top surface 412 ′.
- the increased cavity 418 ′ size of the negative mold 410 ′ now includes space between the one or more sidewalls 316 of the first porous wick layer 310 and the one or more sidewalls 416 ′ of the negative mold 410 ′ extending around a perimeter of the base surface 414 ′.
- Metal particles 366 are introduced within the space between the one or more sidewalls 416 ′ and one or more sidewalls 316 . Then a corresponding positive mold 420 ′ interfaces with the negative mold 410 ′, as shown in FIG. 10 .
- a thermally conductive plate 368 may be introduced between the positive mold 420 ′ and the metal particles 366 prior to sintering.
- FIG. 11 depicts a cross-section of the resulting multi-layer porous wick structure 300 ′.
- the multi-layer porous wick structure 300 ′ comprises a first porous wick layer 310 defining the cap wick layer, the second porous wick layer 320 defining the base wick layer, a plurality of porous liquid supply posts 330 , a plurality of through-holes 340 defining vapor vents within the cap wick layer and a liquid supply wick 370 coupled to the cap wick layer and the base wick layer.
- a negative mold 610 of a first mold set 600 is depicted.
- the negative mold 610 comprises a first surface 612 , a second surface 614 , one or more sidewalls 616 , a plurality of holes 618 and optionally a plurality of dimples 650 .
- the second surface 614 is offset from the first surface 612 .
- the one or more sidewalls 616 extend around a perimeter of the second surface 614 and between the first surface 612 and the second surface 614 .
- the second surface 614 and the one or more sidewalls 616 define a cavity 622 in the first surface 612 of the negative mold 610 of the first set of molds 600 .
- the cavity 622 depicted in FIG. 12 has a perimeter generally defined by a square and has a generally planar second surface 614 . However, in other embodiments the cavity 622 may have a perimeter defined by a circle or other closed shape.
- the plurality of holes 618 extend from the second surface 614 into the negative mold 610 , i.e., generally away from a plane defined by the first surface 612 .
- the plurality of holes 618 are cavities for forming the plurality of porous liquid supply posts 530 as described herein.
- the plurality of holes 618 may vary is shape and size depending on the design requirements needed to increase or decrease capillary action through the plurality of porous liquid supply posts 530 to portions of the base wick layer or the need to increase or decrease surface area available for boiling and evaporating cooling fluid from the base wick layer.
- the shape and size of the plurality of holes 618 may be determined in response to mitigating localized hotspots of the base wick layer.
- the plurality of dimples 650 form surface enhancement features 550 in the first porous wick layer 510 defining the base wick layer in FIG. 12 .
- the surface enhancement features 550 may comprise a variety of sizes, shapes and locations within the multi-layer porous wick structure.
- metal particles 566 are introduced in the cavity 622 of the negative mold 610 of the first mold set 600 .
- the positive mold 620 of the first mold set 600 interfaces with the negative mold 610 of the first mold set 600 for sintering of the metal particles 566 as shown in FIG. 14A .
- FIG. 14B a cross-section of FIG. 14A is depicted.
- an optional copper plate 568 is included between the positive mold 620 and the metal particles 566 prior to sintering.
- the copper plate 568 may form an evaporator layer that contacts the heat-generating device or is optionally used to form the vapor chamber apparatus.
- a negative mold 810 of the second mold set 800 receives the first porous wick layer 510 .
- the first porous wick layer 510 may be attached a copper block 815 or a copper plate. Therefore, in some embodiments, the negative mold 810 of the second mold set 800 may comprise a number of sections to be assembled about the first porous wick layer 510 .
- the negative mold 810 shown in FIG. 16 includes four sections capable of being assembled about the first porous wick layer 510 . While FIG.
- filler particles are introduced to form a sacrificial layer 562 (as shown in FIG. 18B ) with the first porous wick layer 510 as described above.
- metal particles 566 are introduced with the sacrificial layer 562 where at least the tops 536 of the plurality of porous liquid supply posts 530 are exposed with the surface of the sacrificial layer 562 .
- a positive mold 820 of the second mold set 800 is brought into contact with the metal particles 566 .
- the metal particles 566 are sintered with the first porous wick layer 510 and the sacrificial layer 562 in the example assembly of the second mold set 800 depicted FIG. 19 .
- the resulting multi-layer porous wick structure 500 comprises a first porous wick layer 510 defining a base wick layer coupled to a second porous wick layer 520 defining a cap wick layer through the plurality of porous liquid supply posts 530 extending between and forming interstitial spaces between the base wick layer and cap wick layer of the multi-layer porous wick structure.
- the second porous wick layer 520 lacks vapor vents.
- the vapor vents may be formed by machining, for example, without limitation, with a laser cutting system.
- a suitable but non-limiting laser-cutting system is produced by Universal Laser and commercially available under the trademark PLS6MW Multi-Wavelength Laser Platform, and is capable of cutting feature sizes with microscale lateral resolution (tens of microns).
- the resulting multi-layer porous wick structure coupled to a copper block 815 is depicted in FIG. 21 .
- the copper block 815 is replaced with a metal plate, which is optionally a copper plate, and in yet further embodiments, the multi-layer porous wick structure 500 is decoupled from the copper block 815 after sintering.
- the multi-layer porous wick structure 500 may further be assembled with components of a vapor chamber or the components of a vapor chamber may be formed along with the fabrication of the multi-layer porous wick structure 500 .
- FIGS. 22 to 25 depict the formation of a liquid supply wick 570 with the first porous wick layer 510 defining the base wick layer and the second porous wick layer 520 defining the cap wick layer in light forming the multi-layer porous wick structure form the base wick layer to the cap wick layer.
- the forming mold 830 provides the cavities 832 for receiving filler particles to fabricate a sacrificial layer 562 that extends above the plurality of porous liquid supply posts 530 in defined sections while maintaining exposure to at least the tops 536 of the plurality of porous liquid supply posts 530 for coupling to the metal particles 566 when forming the second porous wick layer 520 .
- FIG. 23 depicts the resulting sacrificial layer 562 formed with the first porous wick layer 510 .
- the first porous wick layer 510 is also coupled to a copper plate 568 defining an evaporator plate of a vapor chamber.
- the first porous wick layer 510 including the sacrificial layer 562 may then be configured with a negative mold 810 ′ of a third mold set 800 ′.
- the negative mold 810 ′ comprises a cavity defined by a base surface 814 ′ offset from a negative mold top surface 812 ′ enclosed by one or more sidewalls 816 ′ extending around a perimeter of the base surface 814 ′ and between the base surface 814 ′ and the negative mold top surface 812 ′.
- the increased cavity size of the negative mold 810 ′ includes space between the one or more sidewalls 516 of the first porous wick layer 510 and the one or more sidewalls 816 ′ of the negative mold 810 ′ extending around a perimeter of the base surface 814 ′.
- FIG. 25 depicts the resulting multi-layer porous wick structure 500 ′.
- the multi-layer porous wick structure comprises a first porous wick layer 510 defining the base wick layer, the second porous wick layer 520 defining the cap wick layer, a plurality of porous liquid supply posts 530 , a plurality of through-holes 540 defining vapor vents within the cap wick layer and a liquid supply wick 570 coupled to the cap wick layer and the base wick layer.
- the method further generally include providing a second mold set comprising a negative mold configured to receive the first porous wick structure and a positive mold, introducing particles to form a sacrificial layer with the first porous wick structure in the negative mold of the second mold set, introducing metal particles with the sacrificial layer and the first wick structure in the negative mold of the second mold set and sintering the metal particles in the negative mold of the second mold set where pressure is applied to the metal particles by the positive mold of the second mold set.
- the sintering of the metal particles in the negative mold of the second mold set form a second porous wick layer coupled to the porous liquid supply posts of the first porous wick layer.
- the aforementioned general fabrication method may be further defined to accommodate variations in fabricating a multi-layer porous wick structure from a base wick layer to a cap wick layer or a cap wick layer to a base wick layer. Additionally, fabrication methods may include molds for forming vapor vents in the cap wick layer or liquid supply wicks coupling the base wick layer and the cap wick layer or surface enhancement features.
Abstract
Description
Claims (15)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US15/722,589 US10495387B2 (en) | 2017-03-10 | 2017-10-02 | Multi-layer wick structures with surface enhancement and fabrication methods |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201762469784P | 2017-03-10 | 2017-03-10 | |
US15/722,589 US10495387B2 (en) | 2017-03-10 | 2017-10-02 | Multi-layer wick structures with surface enhancement and fabrication methods |
Publications (2)
Publication Number | Publication Date |
---|---|
US20180259268A1 US20180259268A1 (en) | 2018-09-13 |
US10495387B2 true US10495387B2 (en) | 2019-12-03 |
Family
ID=63444568
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US15/722,589 Expired - Fee Related US10495387B2 (en) | 2017-03-10 | 2017-10-02 | Multi-layer wick structures with surface enhancement and fabrication methods |
Country Status (1)
Country | Link |
---|---|
US (1) | US10495387B2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10700036B2 (en) * | 2018-10-19 | 2020-06-30 | Toyota Motor Engineering & Manufacturing North America, Inc. | Encapsulated stress mitigation layer and power electronic assemblies incorporating the same |
US11712766B2 (en) | 2020-05-28 | 2023-08-01 | Toyota Motor Engineering And Manufacturing North America, Inc. | Method of fabricating a microscale canopy wick structure having enhanced capillary pressure and permeability |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109874268B (en) * | 2018-11-27 | 2020-11-10 | 奇鋐科技股份有限公司 | Manufacturing method of heat dissipation unit |
CN111414056A (en) * | 2019-01-08 | 2020-07-14 | 达纳加拿大公司 | Ultra-thin two-phase heat exchanger with structured wicking |
US11466358B2 (en) * | 2019-12-13 | 2022-10-11 | Arizona Board Of Regents On Behalf Of Arizona State University | Method of forming a porous multilayer material |
US11235404B2 (en) * | 2020-03-21 | 2022-02-01 | International Business Machines Corporation | Personalized copper block for selective solder removal |
US20230184498A1 (en) * | 2021-12-14 | 2023-06-15 | Amulaire Thermal Technology, Inc. | Immersion-type heat dissipation substrate having microporous structure |
EP4246077A1 (en) * | 2022-03-14 | 2023-09-20 | Abb Schweiz Ag | A vapor chamber |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20100307003A1 (en) | 2007-07-27 | 2010-12-09 | Amulaire Thermal Technology, Inc. | Vapor chamber structure with improved wick and method for manufacturing the same |
US20110240264A1 (en) | 2010-03-31 | 2011-10-06 | Fu Zhun Precision Industry (Shen Zhen) Co., Ltd. | Plate-type heat pipe and method for manufacturing the same |
US8720530B2 (en) | 2006-05-17 | 2014-05-13 | The Boeing Company | Multi-layer wick in loop heat pipe |
US20150159511A1 (en) * | 2011-08-30 | 2015-06-11 | Mikro Systems, Inc. | Method of Forming a Thermal Barrier Coating System with Engineered Surface Roughness |
US9455177B1 (en) | 2015-08-31 | 2016-09-27 | Dow Global Technologies Llc | Contact hole formation methods |
-
2017
- 2017-10-02 US US15/722,589 patent/US10495387B2/en not_active Expired - Fee Related
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8720530B2 (en) | 2006-05-17 | 2014-05-13 | The Boeing Company | Multi-layer wick in loop heat pipe |
US20100307003A1 (en) | 2007-07-27 | 2010-12-09 | Amulaire Thermal Technology, Inc. | Vapor chamber structure with improved wick and method for manufacturing the same |
US20110240264A1 (en) | 2010-03-31 | 2011-10-06 | Fu Zhun Precision Industry (Shen Zhen) Co., Ltd. | Plate-type heat pipe and method for manufacturing the same |
US20150159511A1 (en) * | 2011-08-30 | 2015-06-11 | Mikro Systems, Inc. | Method of Forming a Thermal Barrier Coating System with Engineered Surface Roughness |
US9455177B1 (en) | 2015-08-31 | 2016-09-27 | Dow Global Technologies Llc | Contact hole formation methods |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10700036B2 (en) * | 2018-10-19 | 2020-06-30 | Toyota Motor Engineering & Manufacturing North America, Inc. | Encapsulated stress mitigation layer and power electronic assemblies incorporating the same |
US10879209B2 (en) | 2018-10-19 | 2020-12-29 | Toyota Motor Engineering & Manufacturing North America, Inc. | Encapsulated stress mitigation layer and power electronic assemblies incorporating the same |
US11712766B2 (en) | 2020-05-28 | 2023-08-01 | Toyota Motor Engineering And Manufacturing North America, Inc. | Method of fabricating a microscale canopy wick structure having enhanced capillary pressure and permeability |
Also Published As
Publication number | Publication date |
---|---|
US20180259268A1 (en) | 2018-09-13 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US10495387B2 (en) | Multi-layer wick structures with surface enhancement and fabrication methods | |
US11201102B2 (en) | Module lid with embedded two-phase cooling and insulating layer | |
US7578338B2 (en) | Heat dissipating apparatus having micro-structure layer and method of fabricating the same | |
US11428475B2 (en) | Additively manufactured structures for thermal and/or mechanical systems, and methods for manufacturing the structures | |
US20140369005A1 (en) | Passive thermal management device | |
US6935022B2 (en) | Advanced microelectronic heat dissipation package and method for its manufacture | |
US7603775B2 (en) | Heat spreader with vapor chamber and method of manufacturing the same | |
US20100326630A1 (en) | Heat spreader with vapor chamber and method for manufacturing the same | |
US20070017814A1 (en) | Heat spreader with vapor chamber defined therein and method of manufacturing the same | |
WO2017100568A2 (en) | Vapor chamber heat spreaders and methods of manufacturing thereof | |
CN112033197B (en) | Temperature equalizing plate and manufacturing method thereof | |
US11740029B2 (en) | Vapor chamber | |
WO2020123683A1 (en) | Additive manufactured heat sink | |
WO2020195301A1 (en) | Electronic device | |
JP2022013305A (en) | Heat conduction member and manufacturing method of the same | |
WO2022025249A1 (en) | Heat conduction member | |
WO2022025257A1 (en) | Heat conducting member | |
JP2023123890A (en) | Heat conduction member | |
WO2022025253A1 (en) | Heat conducting member | |
WO2022025261A1 (en) | Heat conduction member | |
WO2022025251A1 (en) | Heat conduction member | |
JP2023127013A (en) | Heat conductive member | |
JP2023127009A (en) | Heat conductive member | |
JP2023127008A (en) | Heat conductive member | |
JP2023127010A (en) | Heat conductive member |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: TOYOTA MOTOR ENGINEERING & MANUFACTURING NORTH AME Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:ZHOU, FENG;DEDE, ERCAN MEHMET;REEL/FRAME:043757/0456 Effective date: 20170310 |
|
FEPP | Fee payment procedure |
Free format text: ENTITY STATUS SET TO UNDISCOUNTED (ORIGINAL EVENT CODE: BIG.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NOTICE OF ALLOWANCE MAILED -- APPLICATION RECEIVED IN OFFICE OF PUBLICATIONS |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
AS | Assignment |
Owner name: TOYOTA JIDOSHA KABUSHIKI KAISHA, JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TOYOTA MOTOR ENGINEERING & MANUFACTURING NORTH AMERICA, INC.;REEL/FRAME:051480/0848 Effective date: 20191219 |
|
FEPP | Fee payment procedure |
Free format text: MAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
LAPS | Lapse for failure to pay maintenance fees |
Free format text: PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20231203 |